1. Field of the Invention
The present invention relates generally to the field of optics. More specifically, it relates to the field of microscopy. Even more specifically, it relates to the field of stereoscopic microscopy. Even more specifically, it relates to the field of digitally controlled stereo microscopy, wherein the image is transmitted to a computer screen and the magnication, zoom, and focus is controlled through a software based interface.
2. Description of the Prior Art
One of the major problems inherent in the type of microscopy wherein a fixed objective in combination with two movable lenses or lens sets are used to zoom and focus the image on the stage is that the manual controls for these devices are extremely difficult to manufacture and are very delicate, adding to both the cost of the device and subsequent breakdowns and repairs. This is because the distances between the movable lenses and the stationary lenses that they cooperate with each other to move between low and high zoom are not linear. As the user zooms in on the image through the fixed objective, from low to high, a graphed comparison measuring distance between the lower movable lens or lens set and its respective lower stationary lens or lens set and the corresponding movable and stationary upper lens or lens set become less and less iear, especially at higher magnifications Thus eccentric threading, cams, and the like must be used to allow the user to precisely control the zoom while focusing the image. Additionally, the present invention addresses the problem that in existing microscopy systems that use this movable lens pair or pairs system to zoom in and out and focus on the resultant image, remote control is very difficult and slow, if not impossible. The present invention, by supplying a smooth, computer controlled zoom and focus system over the range provided by the objective makes such tasks at a remote location simple. Combined with a stage movable on an X-Y axis under the same computer control along with a vertical control of the optics module, microscopic level inspections of silicon wafers, biological subjects, metallurgical samples, or other similar objects may be accomplished at the remote location Simultaneous movement of both lenses or lens sets is provided by a software routine that uses a lookup table or the like to set the precise axial distance between the controlled optic stages to provide a focused image at a desired magnification or zoom level In the preferred embodiment, video cameras transfer the image to a computer screen where the user is also controlling the magnification and zoom. Additionally, using multiplexed, "frame sequenced" images along with a wireless stereoscopic switching glasses cycling at 120 times per second, a live, high definition stereoscopic image is made available to the user. Thus, the instant invention provides a valuable tool for applications such as telemedicine, remote operation and/or inspection, defect and failure analysis, quality control, and learning at a distance. Additionally, people with disabilities using special computer controls, can do valuable work that they were previously unable to do.
During a search at the U.S. Patent and Trademark Office, a number of relevant patents were uncovered and they will be discussed below.
First is U.S. Pat. No. 3,818,125 issued on Jun. 18, 1974 to James F. Butterfield. This discloses a stereo television microscope where the two slightly different images are alternated and the viewer, looking through a stereo mask, perceives a three dimensional image. This is completely unlike the present invention in that no teaching of the software controlled positional settings of the movable lens sets is taught.
U.S. Pat. No. 3,873,182 issued on Mar. 25, 1975 to Hidehio Furuhasi discloses a magfication varying device in an optical instrument. This is also dissimilar from the present invention in that no teaching of the simultaneously changing distance between a pair of movable lens sets is set out.
In U.S. Pat. No. 4,195,903 issued to Suminosuke Kawase et al. on Apr. 1, 1980 there is disclosed a binocular microscope with lenses rotatable in the plane of the optical axes. Unlike the present invention, axial distance between sets of lens pairs in unchanged.
An automatic focusing device is disclosed in U.S. Pat. No. 4,447,717 issued to Massao Nohda on May 8, 1984. This is an automatic focusing device that uses a position sensor on the sample, unlike the present invention.
In U.S. Pat. No. 4,653,878 issued to Kanae Nakasato on Mar. 31, 1987 there is disclosed a microscope equipped with a device for driving the revolver and the stage. This is accomplished with a photosensor, unlike the present invention.
U.S. Pat. No. 4,705,367 issued on Nov. 10, 1987 to Alan C. Eckbreth et al. discloses an optical system having a variable focal length. Unlike the present invention, there is no teaching of the lens sets or the look-up table.
In U.S. Pat. No. 4,744,642 issued to Makoto Yoshinaga et al. on May 17, 1987 there is disclosed a microscope. In this system, the objective is movable in relation to the sample. This is clearly unlike the present invention.
In U.S. Pat. No. 5,054,896 issued on Oct. 8, 1991 to H. Jay Margolis there is disclosed a continuously focusable microscope. There are three lenses or sets of lens, which is dissimilar from the instant invention.
U.S. Pat. No. 5,307,202 issued to Ronald J. Martino et al on Apr. 26, 1994 discloses a copy port wherein digital stored images may be manpulated, stored, or viewed through eyepieces. No teaching of the look-up table for the automatic setting of focal distance between the lenses is seen.
U.S. Pat. No. 5,394,267 issued on Feb. 28, 1995 to Toyo Hanzawa discloses a stereomicroscope. Unlike the present invention, this invention utilizes eyepieces and a single objective lens.
An accessory for a stereo microscope is disclosed in U.S. Pat. No. 5,537,248 issued to Ulrich Sander on Jul. 16, 1996. This invention is directed at pivotal optical elements, which is clearly dissimilar from the present invention.
U.S. Pat. No. 5,539,572 issued on Jul. 23, 1996 to Gary Greenberg et al. discloses a microscopic Iumiation and viewing system Unlike the present invention, there is no teaching of the paired fixed and movable lenses or lens sets.
U.S. Pat. No. 5,661,598 issued on Aug. 26, 1997 to Ken Tomioka discloses a optical instrument with a single eyepiece unit. This is clearly unlike the construction of the instant invention.
U.S. Pat. No. 5,663,834 issued to Noburu Koizumi on Sep. 2, 1997 discloses a zoom lens system dissimilar from the present invention in that it has a single fixed ens group and a pair of movable lens groups.
U.S. Pat. No. 5,668,660 issued on Sep. 16, 1997 to Gary D. Hunt discloses a microscope with a plural zoom lens assembly. Unlike the present invention, this includes a selectively movable prism in the optical path.
An electrically driven microscope is disclosed in U.S. Pat. No. 5,706,127 issued to Hiroko Saito et al. on Jan. 6, 1998. Unlike the present invention, there is no teaching of the paired fixed and movable lenses or lens sets of the instant invention.
U.S. Pat. No. 5,729,382 issued on Mar. 17, 1998 to Kazuo Morita et al. discloses a stereoscopic microscope. As with many of the other patents discussed above, there is no teaching of the look-up table and the automatic focal length setting.
Another patent of interest is U.S. Pat. No. 5,825,532 issued on Oct. 20, 1998 to Ryo Mochizuki et al. This discloses a microscopic system integrated with a wide screen television. None of the control features of the instant invention are taught.
In U.S. Pat. No. 5,825,535 issued to Klaus Biber et al. there is shown a pancratic magnification system that is unlike the present invention in that there is no teaching of the computer controlled lens set adjustments.
Lastly, U.S. Pat. No. 5,949,574 issued on Sep. 7, 1999 to Hans-Georg Kapitza discloses a computer supported video microscope. Unlike the present invention, there is no teaching of the paired fixed and movable lenses or lens sets.
Thus, while the foregoing overview of prior art indicates it to be well known to digitally control microscopes and to use similar types of lens arrangements it is not seen that the novel control system and construction of the present invention is taught either singly or in combination by any of the art of record.